Felt material of layer of fine denier felt and layer of coarse denier felt
AssigneeInsituform International N.V.
InventorEric Wood
Life of this patent
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Abstract
The present invention relates to the provision of a filling material such as an inorganic filler in the felt, especially a needled felt. The resulting felt material is formed into a tube for use in a passageway lining process in which the felt material is soaked in a curable resin. The purpose of the filling material is to reduce the quantity of resin required to impregnate the felt, thereby to reduce the cost of the process.
Claims3
A felt material comprising (a) at least one layer of felt of fine denier, (b) at least one layer of felt of coarse denier, and (c) a filling material having a specific gravity substantially the same as that of said felt.
Dependencies are inferred from the claim text.